Robust Picosecond writing of a Layered Antiferromagnet by Staggered Spin-Orbit-Fields

Abstract

Ultrafast electrical switching by current-induced staggered spin-orbit fields, with minimal risk of overshoot, is shown in layered easy-plane antiferromagnets with basal-plane biaxial anisotropy. The reliable switching is due to the field-like torque, relaxing stringent requirements with respect to precision in the time-duration of the excitation pulse. We investigate the switching characteristics as a function of the spin-orbit field strength, pulse duration, pulse rise and fall time and damping by atomistic spin dynamics simulations and an effective equation of motion for the antiferromagnetic order-parameter. The condition, determining the critical spin-orbit field strength for switching is determined and we go on to show that robust picosecond writing is possible at feasible current magnitudes.